Air charging and air volume control for water systems



Sept. 8, 1953 A. F. HANCY AIR CHARGING AND AIR VOLUME CbNTROL FOR WATER SYSTEMS Filed June 21 1950 INVENTOR. AI. LAN E HA/VGY m K ATTORNEY Patented Sept. 8, 953 I 2 51 250 UNITED STATES PATENT OFFICE AIR CHARGING AND AIR VOLUME CONTROL FOR WATER SYSTEMS Allan F. Hancy, Seneca Falls, N. Y., assignor to Goulds Pumps, Inc., Seneca Falls, N. Y., a corporation of New York Application June 21, 1950, Serial No. 169,377

3 Claims. (01. 103-6) 1 My invention relates to domestic water sysefiiciency of the jet pump but also, upon sufliliems and more particularly an air charging cient accumulation, causing the centrifugal pump and air volume control for use in connection with to become airbound. such systems for supplyin h pneumatic pres- The above difficulties in connection with supsure tank of such systems with air and a control 5 plying air to the pneumatic tank by drawing the so as to maintain an adequate controlled volume air through the suction of the centrifugal pump of air in the pneumatic tank at all times. has led to numerous attempts to provide air Water supply systems of the type now in charging devices for the pneumatic tank in Wide use on farms and other districts that do which the air does not pass through the cennot have a community water supply system retrifugal pump but is drawn into the system from quire for their proper operation a volume of air atmosphere by various types of devices on the under pressure above the water in the pneumatic discharge side of the pump. All of such systems tank. This volume of air is essential to force with which I am familiar are expensive to build, the water from the pneumatic tank to the supdifiicult to maintain and subject to breakdown ply outlets during periods when the pump is not in service. The systems which draw air through in operation. Water, particularly when under the suction of the pump are still the simplest pressure, absorbs air and the greater the presto construct and operate if the volume of air sure the more air is absorbed. This absorbed admitted to the suction can be controlled.

air passes with the water to the discharge out- An object of my invention is to provide an lets and must be replenished or the system beair charging and air volume control for a docomes inoperative. mestic water system which is economical to build,

The automatic maintenance of a volume of substantially foolproof in operation and autoair under pressure in pneumatic tanks is not matically maintains the correct volume of air difficult when the pump used in the system is of in the pneumatic tank at all times. the positive displacement type. Such pumps will Another object of my invention is to provide handle large volumes of air and handle that air an air charger designed to introduce air into without the efiiciencyof the pump being greatly the system only when it is needed and introduce affected. However, when centrifugalpumps are such air at the suction of the centrifugal pump employed in such systems, either alone or in a in such minute quantities that the centrifugal combination with a jet pump, the problem bepump efliciency', capacity and the pressure procomes more difficult. The efficiency, capacity ducing ability thereof is not adversely affected and pressure producing ability of acentrifugal to any substantial degree. pump is adversely affected when air is drawn My invention further contemplates the provithrough the suction of the pump. A subsion of a float actuated air volume control which atmospheric pressure exists at the suction of admits air to the suction side of the centrifugal the centrifugal pump during a portion of. the pump, together with provision of means in the pumping cycle in both deep and shallow well jet line between the air inlet from atmosphere to centrifugal systems. The air under subatmosthe suction of the centrifugal pump, preferably pheric pressure conditions expands adjacent the located above the water zone, and serving to so suction of the pump and even when the air is 40 restrict the flow of air to the suction of the cenadmitted in relatively small quantities not only trifugal pump that the efficiency of the centrifuis the efiiciency of the centrifugal pump adversely gal pump, the volume of water which it will hanaffected by drawing the air through the cendle and its pressure producing ability is not adtrifugal pump but also, under certain conditions versely affected to any substantial degree.

of operation'and when the volume of air taken 4 Other objects and advantages of my invention in at the suction is relatively large, the pump will be set forth in the claims and will be apmay cease to pump any reasonable quantity of parent from the following description, when; water and in fact may temporarily or permataken in connection with the accompanying nently lose its prime. In addition, of course, drawings, in which:

in such systems that do not employ a means for Fig. 1 is a side elevation, partially in section, removing the air discharged bythe centrifugal showing a jet centrifugal shallow well domestic pump before a part of the wateris returned to water system including a pneumatic tank in conthe jet pump-for energizing that element, the nection with which the air charging control deair recirculated to the jet pump accumulates in vice of my invention may be employed;

the system not only adversely afiecting the Fig. 2 is a front elevation of a part of Fig. 1;

Fig. 3 is a sectional view taken substantially on the line 33 of Fig. 2 in the direction indicated by the arrows showing the preferred point of attachment of the air charging control device of my invention when it is employed in connection with a shallow well jet centrifugal domestic water system;

Fig. 4 is a view partly in section showing the air .flow limiting device of my invention in assembled relation with its associated parts.

Fig. 5 is a view of the air flow limiting device of Fig. 4 looking from the left of that view;

Fig. 6 is a sectional view showing the member or fitting which is placed in the line between the air inlet and the suction of the centrifugal vpump preferably above the water line; and

Fig. 7 is an enlarged view of a portion of Fig. 4.

In the drawings, I have shown the air changing and air volume control of my invention as applied to a jet centrifugal system of a particular type. This is solely for purposes of illustration as the air charging control device of my invention may be employed in connection with a centrifugal pump per se; with shallow well jet centrifugal systems of a type differing from that specifically shown in this application; and also may be employed with any general type of deep well jet centrifugal system wherein the jet pump is located the well as shown, for example, in the co-pending application of John Mann, Serial No. 614,052, filed September 1, 1945, and entitled Water System, issued to Patent No. 2,619,036 on November 25, 1952.

The water system shown in the drawings with which the air charging control of my invention may be employed comprises a pump assembly generally indicated by the numeral li, a driving motor i2 anda pneumatic pressure tank i3. In the drawings, I have shown a rotatable pump impeller ['4 of the centrifugal preferably closed vane type although it will be appreciated that other types of rotatable impeller non-positive displacement pumps may be employed. In fact, if desired, the air volume control device of my invention may be employed with a positive displacement pump although its use with that type of pump is unnecessary as previously mentioned. The impeller is mounted 'onxthe .endof a shaft it which may be an extension of the motor shaft. An adaptor li lies or ismounted between the end of the motor and the pump assembly to which the pump assembly is bolted, as indicated at 18, the adaptor carrying part of the pump'housing '20.

The centrifugal pump, preferably of the selfpriming type, is provided with the usual series-of curved vanes, the impeller being mounted in a casing 19 formed around the impeller in any suitable manner.

Water from the well is drawn into the pump through a suction pipe 2| which extends into the well, the suction pipe 21 being connected to a chamber 22. In suitable bores provided in a casting 23 which constitutes part of the housing there are mounted a nozzle '24 and a diffuser 26. The nozzle 23 and the "diffuser 2'6 constitute a jet pump, the function and operation of which are well known in the art to which this invention applies. A suitable threaded cap 21 is provided around the extended end of the diiT-user which upon removal enables access to the diffuser and the nozzle. Between the cap 21 and the external walls of the diffuser 26, an annular passage 28 is provided which connects with a centrifugal pump suction chamber 29.

The centrifugal pump suction chamber 29 connects with a tubular element 3! which opens into the eye 32 of the impeller 14. The centrifugal pump 14 discharges through suitable diffusion vane openings (not shown) in the pump casing into a chamber 33' which is divided from a chamber 34 by a wall 36. The wall between the chambers has :an opening 31 for the passage of liquid from the "chamber 33 to the chamber 36. The chambers 33 and 34 constitute an air separation and discharge chamber to enable water and separated air to flow through a discharge fpipe .tfiwhile substantially air free water returns througha passage 39 (Fig. 3) formed in the casting .23 to the nozzleof the jet pump. The water supplied to thejet pump supplies the necessary energy for lifting the water through the suction pipe 2'! from the source of supply or rather creating :a =-subatmospheric pressure in the pipe 2i whereby the pressure of air on the surface of the liqu'i'd'in the source of supply may force the water up the suction pipe 2 I.

The foregoing specific description of a suitable jet centrifugal pump is merely by way of example. The air charging and volume control system of my invention may be employed with other types of shallowwell jet centrifugal pumps; may be employed with conventional centrifugal pumps used in connection with water systems; and may be employed in connection with deep well 'jet centrifugal systems as will be apparent. When the specific system shown herein is employed for deep well operation the nozzle 24 and the diffuser '26 are removed, a solid plug substituted for the nozzle 24 and the passage 39 is connected by a pressure pipe to the jet pump now located adjacent the bottom of the well. A suction pipe is then connected between the discharge of the jet pump and the chamber 29. The discharge pipe as shown in the drawings leads directly to the pneumatic tank 13. If necessary as in the case of a 'deep well system a pressure control valve may be mounted in this pipe.

The air charging and air volume control system of my'invention comprises a tubular air conduit 41 (Figs. 1 and '2) which may be flexible copper tubing which is connected by a threaded fitting, to a check valve 12 inserted in the casting 23 which opens into the centrifugal pump suction chamber 29 as shown most clearly in Fig. 3. If desired the conduit ll may be connected to the jet pump suction chamber 22 although this is a less desirable arrangement. The check valve Q2 may bed the automobile tire type and is for the purpose "of preventing water from flowing through the conduit when a pressure exists in chamber 29.

The conduit 4i connects with' a fitting, generally indicated'by the numeral 44 (Figs. 1 and 6), which is connected by a short pipe with an air inlet valve assembly, generally indicated by the numeral 46. The body of the air valve has a plurality of openings 47 and the upper end thereof extends into a chamber formed in .a member 49 the stem of the valve projecting into the chamher, as indicated at 51. The valve requires no further description since it is of the common automotive tire type. If desired the member 49 may be ported to atmosphere, the openings 41 omitted and air admitted around the stem of the valve.

The member 49 is threaded for reception in a threaded opening 52 formed in the tank side wall.

The opening 52 is so located with respect to the height and volumetric capacity of the pneumatic t n th t it l es at the normal level of liquid in the tank necessary to maintain a proper volume of air above the liquid to provide optimum operating conditions for forcing waterto the outlet faucets of the water system when the pump is not operating.

A float 54 is carried by a float stem 56. The float stem 56 is enlarged at its outer end and extends through the opening 52 in-the tank wall and into the chamber of the member 49 with the outer enlarged end 51 thereof in engagement with the valve stem 5 I. The enlarged end of the float stem 56 extends through a suitable rubber diaphragm 53 which prevents leakage of water or air from the pneumatic tank.

The fitting or member 44, are shown most clearly in comprises a fitting body GI which is provided with a threaded bore 62 into which is threaded as indicated at 63 a fitting 64 which is connected to the short length of pipe 65. Suitable means as indicated at 66, as well known in the art, are adapted to connect the short length of pipe 65 with the fitting 64.

The .bore 62 in the fitting body 6| is connected with a cross bore 68 which is accurately bored to a predetermined diameter. The outer end of the fitting body 6| has an extension which is provided with threads 69 which by suitable means as indicated at H is connected to the air inlet tube 4|. A pin 12 extends into the bore 68 and is provided with helical threads which cooperate with corresponding threads 13 formed only in the adjacent part of the bore 68. The pin 12 has a slotted head 14 for the reception of a screwdriver and a suitable gasket 76 is provided beneath the head of the pin 12.

It will now be appreciated that the bore 68 constitutes a part of the air conduit from the openings in the valve 46 through the check valve 42 to the suction chamber 29 of the centrifugal pump. During the travel of the air through this conduit the air must travel around the helical path formed between the threaded pin 12 and the cylindrical bore 68. The effective cross-sectional area of this helical path is many times smaller than the cross-sectional area of the conduit 4| In air conduits of this type, it is impossible to prevent clogging of a relatively long length of copper tubing if the tubing is made too small in diameter. Dust particles are drawn in with the air and if a fine, small diameter tubing or orifice is employed, it will clog during normal operation. Moreover, a minute leak in the check valve 42 would admit water, containing foreign substances, to the conduit. When such tubing clogs, it is necessary to remove the tubing and it is a difllcult job to blow out or otherwise clean the tubing. The user of the system usually does not have any means available for freeing the clog in the tubing. Consequently as a practical matter a tubing of a diameter many many times greater than desired or necessary is required. Such large diameter tubing admits more air to the system than is required by reason of the normal absorption of the air by the water in the pneumatic tank.

More important is the fact that when the float rises and opens the air valve, the admission of air is in such large volume that, as previously mentioned, the efficiency, capacity and pressure producing ability of the centrifugal pump is adversely affected. Moreover, in systems where no means is provided for removing the air before the pressure water recirculates to the jet pump, the

the details of which Figs.,4 to 7 inclusive,

efllciency, capacity and head producing ability of the jet pump is adversely affected. If suflicient air is admitted to the system or accumulates in the system the centrifugal pump may either temporarily or permanently become air bound.

With the air charging and air volume control system of my invention, air inlet tubing of normal size may be used which avoids clogging of the air inlet conduit except at the helical path of restriction.

The volume of air admitted to the pneumatic tank or passing through the air conduit may be varied by substituting another pin for the pin 72 having more or less threads per inch than that shown in the drawings. Moreover, a pin may be substituted in which the depth of the threads is increased or decreased from that shown. In addition of course the'same pin 72 may be employed which may be threaded outward from the position shown in the drawings and a thicker gasket 16 substituted so as to decrease the helical path through which the air may flow.

In any event the volume of air admitted may be varied either by varying the cross-sectional area of the helical path or' increasing its length. Of course, restricted paths other than helical paths may be employed. If desired, the means above described for restricting the flow of air to the centrifugal pump may be employed in connection with an air relief on the tank. In such case air is admitted at all times when a subatmospheric pressure exists at the centrifugal pump suction and the air relief on the pneumatic tank opens to allow excess air to escape. Such systems are well known in the art.

It will now be appreciated that I have provided an air charging and volume control system for use particularly with a domestic water system employing a centrifugal pump which is simple in construction, reliable in operation and in which the flow of air to the centrifugal pump may be accurately controlled so that the volume of air admitted does not materially affect the efilciency, capacity or pressure producing ability of the centrifugal pump. If the helical air flow path around the pin 12 should become clogged with particles of dirt, the pin 12 is easily removed for cleaning and the act of removing the pin will draw any particles of dirt out of the bore 68 with the pin, by reason of the threads thereon.

While I have shown and described the preferred form of my invention, it will be appreciated that various changes and modifications may be made therein, particularly in the form and relation of parts, without departing from the spirit of my invention as set forth in the appended claims.

I claim:

1. An air volume control for the pneumatic tank of a domestic water system having a pressure pump for supplying water from the source of supply to the pneumatic tank, in combination, an air conduit connected to the suction of the pump and subject to the subatmospheric pressure existent at said suction at least at times during the operation of the system, an inlet for air from atmosphere to said conduit, means in said conduit for restricting the flow of air through said conduit, said means comprising a fitting having a bore with the bore constituting part of the conduit and a threaded element in said bore providing a restricted helical path for the flow of air and means in said conduit for preventing a flow of liquid from said pump toward said pneumatic tank when a super atmospheric pressure exists at the suction of the pump.

egesagzeo 2. air volume :control for the pneumatic tank of a domestic water system having a pressure pump for supplying water from the source of supply to the pneumatic tank, in combination, an air conduit connected to the suction of the pump and subj'ect'to the subatmospheric pressure existent at said suction at least at times during the operation of the system, an inlet for air from atmosphere to said conduit, means in said conduit for restricting the flow of air through said conduit, said means comprising a fitting having a bore with the boreconstituting part of the conduit and a threaded element in said bore providing a restricted helical path for the flow of air, and means for maintaining the volume of air in said pneumatic tank substantially constant at all times.

3. An air volume control for the pneumatic tank of a domestic water system having a pressure pump for supplying water from the source of supply to the pneumatic tank, in combination, an air conduit connected to the suction of the pump and subject to the subatmospheric pressure existent at said suction at least at times during the operation of the system, an inlet for air from 8 atmosphereto saifi conduit, a waive adjacent said airinlet, a meat in said lpneumatic Ttatnk substantially at the normal liquid lev'el th'er'ein adapted to open said value when the liquid level therein rises above a predetermined level and means iIlSBlld conduit for restricting the flow of air :through said conduit, said "means comprising a fitting having a bore with the bore constituting part of the conduit and :a threaded element in said here providing :a restricted helical path for the flow of air.

ALLAN F. HANCY.

References Cited in the file -of this patent UNITED STATES PATENTS Number Name Date 1,074,098 .Astrom Sept. 30, 1913 1,277,383 Cherry Sept. 3, 1918 1,460,982 Records July 3, 1923 1,913,959 Culp July 18, 1933 2,220,209 Carpenter Nov 5, 1940 2,347,472 iDorward Apr. 25, 1944 2,381,640

Brandstrom Aug. 7, I945 

